1. Field of the Invention
The present invention relates, in general, to document authentication and discrimination. More specifically, the present invention relates to a system for evaluating currency bills and maintaining a record of authentic, counterfeit and/or unidentified bills evaluated by the system.
2. Background
A number of systems have been developed for authenticating the genuineness of currency notes and other security documents. Included among such systems are automated machines having the capability to accommodate a stack of currency bills and/or documents and rapidly evaluate all the bills in the stack. Generally, such machines are equipped with one or more sensors to evaluate one or more characteristics of the documents under test including, for example, magnetic, optical, UV or visible light reflectance or transmissivity characteristics.
Among the more sophisticated of such currency evaluation machines are those which are capable of identifying, discriminating and counting multiple currency denominations. This type of machine, hereinafter designated as a xe2x80x9ccurrency discriminator,xe2x80x9d typically employs optical or magnetic sensors to identify the respective bills in the stack by discriminating between different denominations of currency bills. Currency discrimination is based on the comparison of sensed optical or magnetic characteristics with prestored parameters relating to different denominations of bills, while accounting for adequate tolerances reflecting differences among bills of a given denomination and/or series. Magnetic sensing is based on detecting the presence or absence of magnetic ink in portions of the printed indicia on the currency by using magnetic sensors, usually ferrite core-based sensors, and using the detected magnetic signals, after undergoing analog or digital processing, as the basis for discrimination. The more commonly used optical sensing technique, on the other hand, is based on detecting and analyzing variations in light reflectance or transmissivity characteristics occurring when a currency bill is illuminated and scanned by a strip of focused light.
In addition to determining the denomination of a bill, a currency discriminator may detect suspect or counterfeit bills by sensing characteristic information such as, for example, magnetic, optical, UV or visible light reflectance or transmissivity characteristics, then comparing the sensed information to the expected characteristics of a bill of the same denomination. A document is considered genuine or counterfeit depending on whether the detected data is within an acceptable range of an expected value.
Less sophisticated types of currency evaluation machines, known as xe2x80x9ccounters,xe2x80x9d are not designed to identify or discriminate among multiple currency denominations of bills but rather are designed to rapidly count the number of currency bills in a stack. Because counters are incapable of determining the denomination of bills, they are generally used to evaluate stacks of bills which have already been pre-sorted by denomination such as, for example, a stack consisting entirely of $5 bills or consisting entirely of $100 bills. In some models, the counter may be externally informed of the denomination of bills which it is counting by an operator, so that displays, sensitivity levels, etc. may be adjusted according to the appropriate denomination. For example, counters having been informed of the denomination of bills may include sensors for detecting suspect or counterfeit bills in substantially the same manner as that of currency discriminators, including variation of authentication methods or adjustment of sensitivity levels corresponding to the denomination of the bills to be authenticated.
Whether suspect documents are detected by a currency discriminator or counter, it is desirable to separate the detected suspect documents from genuine documents. This may be accomplished automatically by the currency discriminator or counter, for example, by stopping the machine to permit the operator to remove the suspect documents from the machine immediately after they are detected or by delivering suspect documents to an output receptacle separate from that of genuine documents. Both of these methods are described in co-pending patent application Ser. No. Unknown, Attorney Docket No.:CUMM 190, assigned to the assignee of the present invention and incorporated herein by reference in its entirety.
After removing suspect documents from the currency discriminator or counter, an operator typically places the suspect documents in a separate retaining area for collection and subsequent forwarding to the proper authorities. Generally, it would be desirable if records could be maintained of the suspect documents which have been detected by a particular machine throughout a designated time period. For example, it would be desirable to record how many suspect $100 notes, $50 notes, etc. are received each day. This would enable the operator to monitor the source of suspect documents and, if possible, reduce or eliminate the occurrences of such suspect documents. Recordation of suspect documents may also facilitate subsequent adjustment of sensitivity levels, for example, to increase or reduce the number of suspect notes detected for a particular denomination of currency to a desired amount. Heretofore, however, after detection of suspect documents by a currency discriminator or counter, recordation of the suspect documents has been accomplished, if at all, by the operator in a manual and time-consuming secondary operation. Accordingly, there is a need for a more automated, efficient system of recording suspect documents detected by currency discriminators or counters. The present invention is directed to satisfying these needs.
In accordance with one aspect of the present invention, there is provided a currency discriminator for evaluating currency bills and recording information associated with the evaluated bills. The currency bills to be evaluated are generally unidentified and unauthenticated. The currency bills to be evaluated are transported, one at a time, from an input receptacle to an output receptacle along a transport path. First and second scanheads positioned along the transport path obtain respective first and second types of detected characteristic information from the currency bills being evaluated. A system memory stores first and second types of master characteristic information corresponding to genuine currency bills of assorted denominations and/or series. A microprocessor performs respective first and second comparison tests to identify and determine the authenticity of the currency bills being evaluated, and recording means is provided for maintaining a reviewable record of the first and second comparison tests.
In the first comparison test, for each individual bill under test, the microprocessor evaluates whether the first tape of detected characteristic information obtained from the bill under test sufficiently matches an item of the first type of master characteristic information corresponding to a particular denomination and/or series of bill. If a positive determination is reached in the first comparison test, the microprocessor identifies the denomination and/or series of the bill under test. If a negative determination is reached in the first comparison test, the microprocessor generates a no call error signal indicating that it is unable to identify the denomination and/or series of the bill under test. The transport mechanism may be halted upon each occurrence of a no call error signal to permit removal of the no call bill or document. Information associated with the no call error signal(s) including, for example, times of occurrence or quantities of no call error signal(s) is recorded in system memory for subsequent review.
In the second comparison test, for each individual bill having its denomination and/or series identified by the first comparison test, the microprocessor evaluates whether the second type of detected characteristic information obtained from the bill under test sufficiently matches the second type of master characteristic information corresponding to the denomination and/or series of the bill under test. If a positive determination is reached in the second comparison test, the bill is authenticated as genuine. If a negative determination is reached in the second comparison test, the microprocessor generates a suspect document error signal indicating that the bill under test is suspected to be non-genuine. The transport mechanism may be halted upon each occurrence of a suspect document error signal to permit removal of the suspect bill or document. Information associated with the authenticated or suspect bill(s) including, for example, times of occurrence or quantities of suspect document error signals, as well as the denomination and/or series of the authenticated or suspect bill(s) is recorded in system memory for subsequent review.
In accordance with another aspect of the present invention, there is provided a currency counter for evaluating currency bills and recording information associated with the evaluated bills. The currency bills to be evaluated are generally unauthenticated but have a pre-specified or pre-indicated denomination and/or series. The currency bills to be evaluated are transported, one at a time, from an input receptacle to an output receptacle along a transport path. A scanhead positioned along the transport path obtains detected characteristic information from the currency bills being evaluated. A system memory stores master characteristic information corresponding to genuine currency bills of assorted denominations and/or series. A microprocessor performs respective comparison tests to determine the authenticity of the currency bills being evaluated, and recording means is provided for maintaining a reviewable record of the results of the comparison tests.
In the comparison tests, for each individual bill having a pre-specified denomination and/or series, the microprocessor evaluates whether the detected characteristic information obtained from the bill under test sufficiently matches the master characteristic information corresponding to the denomination and/or series of the bill under test. If a positive determination is reached in the comparison test, the bill is authenticated as genuine. If a negative determination is reached in the comparison test, the microprocessor generates a suspect document error signal indicating that the bill under test is suspected to be non-genuine. The transport mechanism may be halted upon each occurrence of a suspect document error signal to permit removal of the suspect bill or document. Information associated with the authenticated or suspect bill(s) including, for example, times of occurrence or quantities of suspect document error signals, as well as the denomination and/or series of the authenticated or suspect bill(s) is recorded in system memory for subsequent review.